The present application relates to general-purpose input buffers and, more particularly, to low voltage signal input buffers.
There are several well-known problems associated with the typical input buffer. A first problem with prior input buffers is the delay through the input buffer. Alternating Current (AC) buffers are generally faster than Direct Current (DC) buffers, but have problems with stability. DC buffers are generally more stable than AC buffers, but their switching speeds are too slow in many applications.
Another problem with prior input buffers is the switching voltage level is typically off center. Still another problem with prior input buffers is their noise immunity with respect to ground is often unacceptable. Furthermore, often a number of prior input buffers are needed in order to handle different low input voltage ranges.